package com.example.config;

import com.example.common.JacksonObjectMapper;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;

import java.util.List;

@Configuration
public class WebMvcConfiguration extends WebMvcConfigurationSupport {

    @Override
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        super.addResourceHandlers(registry);
        registry.addResourceHandler("/backend/**").addResourceLocations("classpath:/backend/");
        registry.addResourceHandler("/front/**").addResourceLocations("classpath:/front/");
    }

    /**  第二步
     *     处理对象映射器   扩展mvc框架的消息转换器
     * @param converters
     */
    @Override
    protected void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
        //创建消息转换对象
        MappingJackson2HttpMessageConverter messageConverter=new MappingJackson2HttpMessageConverter();
        //设置对象转换器，底层使用Jackson将Java对象转为json
        messageConverter.setObjectMapper(new JacksonObjectMapper());
        converters.add(0,messageConverter);//追加到MVC框架的转换器集合，索引0表示优先使用自己定义的消息转换器
    }
}
